Existing hydraulic tools, such as hydraulic wrenches, generate heat as result of the use of high temperature hydraulic fluid passing through the tool. The user grips a grip which surrounds a metal valve body through which the high temperature hydraulic fluid passes. It is desirable to prevent the transfer of this heat to the user's hand. The prior art insulates the metal valve body with a PVC-based dip, which tends to be inadequate to prevent the passage of heat generated by the high temperature hydraulic fluid. In addition, the PVC-based dip is not very durable and is not easy to replace if the tool becomes damaged.
Prior art tools have controlled flow in a circuit, thereby controlling motor revolutions per minute (rpm) of a hydraulically driven tool, such as a wrench or a drill, which controls the torque of a driven mechanical mechanism, such as used on an impact wrench. A control for setting the revolutions per minute (rpm) to two discrete settings has been used in the prior art. This presents a disadvantage in that only two settings are provided. Other prior art tools have used a pressure compensated flow control mechanism with an infinite adjustment setting. Pressure compensated flow control mechanisms are costly to manufacture.
A hydraulically driven tool is provided herein which provides improvements to existing tools and which overcomes the disadvantages presented by the prior art. Other features and advantages will become apparent upon a reading of the attached specification, in combination with a study of the drawings.